Were Pink Panthers Behind Last Week's Record-Breaking Gem Heist?

There is growing speculation that the $65 million heist of an exclusive London jewelry store was the work of a notorious band of European jewel thieves known to police as the Pink Panthers.

A key element in the speculation is that the men who looted Graff Diamonds on New Bond Street Aug. 6 made no effort to hide their faces, suggesting that they had been able to alter their looks with "Mission Impossible" style prosthetic make-up.

Disguises as well as lightning-quick robberies have been hallmarks of the Pink Panthers who last year dressed as blond women to get past security at the famed Harry Winston's in Paris and swipe $32 million worth of gems and jewelry.

Today, a reward of $1.6 million was offered for information leading to the arrest of the Graff bandits.

"I think this is the biggest reward ever been offered for a crime of this type," said Officer Pam Mace, head of Flying Squad investigating the robbery.

The heist at Graff's, famous for its celebrity clientele like Naomi Campbell and Paris Hilton, included 43 pieces, including watches, earrings, rings and a necklace. There were a total of 272 diamonds in the haul, and the robbery has been calculated to be the world's fourth largest jewelry heist.

The two men were in and out of the store in only minutes, leaving with a woman hostage. They fired one shot into the air to clear the street, let their hostage go and drove off in a BMW. A few blocks later they switched cars again, firing another shot into the ground to keep any gawkers at bay. They switched vehicles a third time to complete their getaway.

London Diamond Thieves, Pink Panther Copycats?

Scotland Yard has refused to comment on any aspect of the investigation, but the makeup artist company Charles Fox has confirmed to ABC News that they are helping police investigators.

The British paper The Sun has reported that a 29-year-old freelance employe of Charles Fox helped the thieves alter their looks by coloring their hair and using liquid latex to change their facial features.

Annie Tagge of Screen Face, a company specialising in professional makeup and special effects for theater and film, explained that she uses "latex to age people for films. The process is really quick and easy." She went on to explain that "anyone could do it to completely change their look." Tagge also noted that the products are not expensive with the liquid latex costing under $20.

Eric Pape, who has researched and written about the Pink Panthers, explained that "a number of the tactics [used] seem to be reminiscent of the Panthers. They usually show up quickly, are very imaginative." He did initially have some doubts noting that "at first I thought it was not imaginative enough and below their [the Pink Panther's] standards until I heard about the rubber faces."

Scott Andrew Selby, co-author of the upcoming book "Flawless: Inside the Largest Diamond Heist in History," isn't convinced it was the Panthers who pulled off the Graff heist, suggesting instead it could be copycats.